Upregulation Of Growth Factors Research Articles

Novel approach for biomaterial assessment: utilizing the Ex Ovo quail cam assay for biocompatibility pre-screening

In recent years, the chorioallantoic membrane (CAM) has emerged as a crucial component of biocompatibility testing for biomaterials designed for regenerative strategies and tissue engineering applications. This study explores angiogenic potential of an innovative acellular and porous biopolymer scaffold, based on polyhydroxybutyrate and chitosan (PHB/CHIT), using the ex ovo quail CAM assay as an alternative to the conventional chick CAM test. On embryonic day 6 (ED6), we placed the tested biomaterials on the CAM alone or soaked them with various substances, including vascular endothelial growth factor (VEGF-A), saline, or the endogenous angiogenesis inhibitor Angiostatin. After 72 h (ED9), we analyzed blood vessels formation, a sign of ongoing angiogenesis, in the vicinity of the scaffold and within its pores. We employed marker for cell proliferation (PHH3), embryonic endothelium (WGA, SNA), myofibroblasts (α-SMA), and endothelial cells (QH1) for morphological and histochemical analysis. Our findings demonstrated the robust angiogenic potential of the untreated scaffold without additional influence from the angiogenic factor VEGF-A. Furthermore, gene expression analysis revealed an upregulation of pro-angiogenic growth factors, including VEGF-A, ANG-2, and VE-Cadherin after 5 days of implantation, indicative of a pro-angiogenic microenvironment. These results underscore the inherent angiogenic potential of the PHB/CHIT composite. Additionally, monitoring of CAM microvilli growing to the scaffold provides a methodology for investigating the biocompatibility of materials using the ex ovo quail CAM assay as a suitable alternative model compared to the chicken CAM platform. This approach offers a rapid screening method for biomaterials in the field of tissue repair/regeneration and engineering.

A bovine model of hypoxia-induced pulmonary hypertension reveals a gradient of immune and matrisome response with a complement signature found in circulation.

Pulmonary hypertension (PH) is a progressive vascular disease characterized by vascular remodeling, stiffening, and luminal obstruction, driven by dysregulated cell proliferation, inflammation, and extracellular matrix (ECM) alterations. Despite the recognized contribution of ECM dysregulation to PH pathogenesis, the precise molecular alterations in the matrisome remain poorly understood. In this study, we employed a matrisome-focused proteomics approach to map the protein composition in a young bovine calf model of acute hypoxia-induced PH. Our findings reveal distinct alterations in the matrisome along the pulmonary vascular axis, with the most prominent changes observed in the main pulmonary artery. Key alterations included a strong immune response and wound repair signature, characterized by increased levels of complement components, coagulation cascade proteins, and provisional matrix markers. Additionally, we observed upregulation of ECM-modifying enzymes, growth factors, and core ECM proteins implicated in vascular stiffening, such as collagens, periostin, tenacsin-C, and fibrin(ogen). Notably, these alterations correlated with increased mean pulmonary arterial pressure and vascular remodeling. In the plasma, we identified increased levels of complement components, indicating a systemic inflammatory response accompanying the vascular remodeling. Our findings shed light on the dynamic matrisome remodeling in early-stage PH, implicating a wound-healing trajectory with distinct patterns from the MPA to the distal vasculature. This study provides novel insights into the molecular underpinnings of PH pathogenesis and highlights potential biomarkers and therapeutic targets within the matrisome landscape.

Reciprocal Dynamics of Metabolism and mRNA Translation in Tumor Angiogenesis.

Angiogenesis, the process of formation of new blood vessels from pre-existing vasculature, is essential for tumor growth and metastasis. Anti-angiogenic treatment targeting vascular endothelial growth factor (VEGF) signaling is a powerful tool to combat tumor growth; however, anti-tumor angiogenesis therapy has shown limited efficacy, with survival benefits ranging from only a few weeks to months. Compensation by upregulation of complementary growth factors and switches to different modes of vascularization have made these types of therapies less effective. Recent evidence suggests that targeting specific players in endothelial metabolism is a valuable therapeutic strategy against tumor angiogenesis. Although it is clear that metabolism can modulate the translational machinery, the reciprocal relationship between metabolism and mRNA translational control during tumor angiogenesis is not fully understood. In this review, we explore emerging examples of how endothelial cell metabolism affects mRNA translation during the formation of blood vessels. A deeper comprehension of these mechanisms could lead to the development of innovative therapeutic strategies for both physiological and pathological angiogenesis.

Senolytic therapy combining Dasatinib and Quercetin restores the chondrogenic phenotype of human osteoarthritic chondrocytes by the release of pro-anabolic mediators.

Cellular senescence is associated with various age-related disorders and is assumed to play a major role in the pathogenesis of osteoarthritis (OA). Based on this, we tested a senolytic combination therapy using Dasatinib (D) and Quercetin (Q) on aged isolated human articular chondrocytes (hACs), as well as in OA-affected cartilage tissue (OARSI grade 1-2). Stimulation with D + Q selectively eliminated senescent cells in both, cartilage explants and isolated hAC. Furthermore, the therapy significantly promoted chondroanabolism, as demonstrated by increased gene expression levels of COL2A1, ACAN, and SOX9, as well as elevated collagen type II and glycosaminoglycan biosynthesis. Additionally, D + Q treatment significantly reduced the release of SASP factors (IL6, CXCL1). RNA sequencing analysis revealed an upregulation of the anabolic factors, inter alia, FGF18, IGF1, and TGFB2, as well as inhibitory effects on cytokines and the YAP-1 signaling pathway, explaining the underlying mechanism of the chondroanabolic promotion upon senolytic treatment. Accordingly, stimulation of untreated hAC with conditioned medium of D + Q-treated cells similarly induced the expression of chondrogenic markers. Detailed analyses demonstrated that chondroanabolic effects could be mainly attributed to Dasatinib, while monotherapeutical application of Quercetin or Navitoclax did not promote the chondroanabolism. Overall, D + Q therapy restored the chondrogenic phenotype in OA hAC most likely by creating a pro-chondroanabolic environment through the reduction of SASP factors and upregulation of growth factors. This senolytic approach could therefore be a promising candidate for further testing as a disease-modifying osteoarthritis drug.

Sex-specific role of RNA-binding protein, pAUF1, on prolonged hypersensitivity after repetitive ischemia with reperfusion injury.

Repetitive ischemia with reperfusion (I/R) injury is a common cause of myalgia. Ischemia with reperfusion injuries occur in many conditions that differentially affect males and females including complex regional pain syndrome and fibromyalgia. Our preclinical studies have indicated that primary afferent sensitization and behavioral hypersensitivity caused by I/R injury may be due to sex-specific gene expression in the dorsal root ganglia (DRG) and distinct upregulation of growth factors and cytokines in the affected muscles. To determine how these unique gene expression programs may be established in a sex-dependent manner in a model that more closely mimics clinical scenarios, we used a developed prolonged ischemic myalgia model in mice whereby animals experience repeated I/R injuries and compared behavioral results with unbiased and targeted screening strategies in male and female DRG. Several distinct proteins were found to be differentially expressed in male and female DRG, including phosphorylated AU-rich element RNA-binding protein (pAUF1), which is known to regulate gene expression. Nerve-specific siRNA-mediated knockdown of AUF1 inhibited prolonged hypersensitivity in females only, whereas overexpression of AUF1 in male DRG neurons increased pain-like responses. AUF1 knockdown was able to specifically inhibit repeated I/R-induced gene expression in females potentially downstream of prolactin receptor signaling. Data suggest RNA-binding proteins such as pAUF1 may underlie the sex-specific effects on DRG gene expression that modulates behavioral hypersensitivity after repeated I/R injury through prolactin signaling. This study may aid in finding distinct receptor differences related to the evolution of acute to chronic ischemic muscle pain development between sexes.

Natural Products in the Treatment of Retinopathy of Prematurity: Exploring Therapeutic Potentials.

Retinopathy of prematurity (ROP) is a vascular disorder affecting the retinas of preterm infants. This condition arises when preterm infants in incubators are exposed to high oxygen levels, leading to oxidative stress, inflammatory responses, and a downregulation of vascular endothelial growth factors, which causes the loss of retinal microvascular capillaries. Upon returning to room air, the upregulation of vascular growth factors results in abnormal vascular growth of retinal endothelial cells. Without appropriate intervention, ROP can progress to blindness. The prevalence of ROP has risen, making it a significant cause of childhood blindness. Current treatments, such as laser therapy and various pharmacologic approaches, are limited by their potential for severe adverse effects. Therefore, a deeper understanding of ROP's pathophysiology and the development of innovative treatments are imperative. Natural products from plants, fungi, bacteria, and marine organisms have shown promise in treating various diseases and have gained attention in ROP research due to their minimal side effects and wide-ranging beneficial properties. This review discusses the roles and mechanisms of natural products that hold potential as therapeutic agents in ROP management.

(098) LOW INTENSITY SHOCKWAVE THERAPY FOR WOMEN WITH SEXUAL DYSFUNCTION

Abstract Introduction Low intensity shockwave therapy (LiSWT) has been used to treat sexual dysfunction by inducing genital tissue mechanotransduction. Mechanotransduction is the ability of a cell to actively convert contraction/expansion mechanical stimuli induced by exposure to the shockwave energy into biochemical signals with physiological effects including synthesis of nitic oxide, upregulation of vascular endothelial growth factors, recruitment of endothelial progenitor cells, vasodilation, and expression of tumor necrosis factor alpha mRNA with anti-inflammatory activity. The greater the shockwave energy absorbed in genital tissues, the greater the opportunity for mechanotransduction physiologic effects to occur and improve sexual function. Therefore, effectiveness of LiSWT depends, in part, on applied energy (mJ/mm2) and number of applications (total shocks). In 2019, our sexual medicine clinic began utilizing the SoftWave (Urogold 100™) LiSWT device, FDA cleared for pain amelioration, connective tissue activation, wound healing, and improved blood flow, to treat individuals with vulvas with sexual dysfunction. Objective To review the various sexual health concerns in individuals with vulvas effectively treated by LiSWT. Methods A chart review was performed of individuals with vulvas with various sexual dysfunctions, including genital pain and genito-pelvic dysesthesia (GPD), who received LiSWT between April 2019 and June 2023. In general, 2400 shocks were applied at energy flux density 0.05-0.08 mJ/mm2, Hz = 3, membrane pressure = 1. The Patient Global Impression of Improvement (PGI-I) was used to assess post-LiSWT outcome; improvement was positive if the post-LiSWT PGI-I ranged from 1-3. Results 189 women, mean age 32 (range 18–67) years, with sexual dysfunction underwent LiSWT treatments in the 38 months. 18 women with neuroproliferative vestibulodynia (NPV) who underwent vestibulectomy received 3-6 post-operative vestibular LiSWT to reduce post-operative pain and improve wound healing; 83% reported improved PGI-I. 24 patients with hormone-mediated vestibulodynia who elected not to use hormone treatment, underwent vestibular LiSWT; 54% reported improved PGI-I. 25 menopausal patients with persistent symptoms of Genito-Urinary Syndrome of Menopause (GSM) received multiple vestibular LiSWT treatments; 64% improved PGI-I, including reduction of urinary incontinence. 36 women with PGAD/GPD from lumbosacral annular tear-and/or Tarlov cyst-induced sacral radiculopathy who were not candidates for minimally invasive spine surgery or continued to have symptoms after recovering from spine surgery, underwent multiple treatments of lumbosacral spine LiSWT; 58% reported improved PGI-I. 86 patients with neuroproliferative vestibulodynia (NPV) underwent 2-3 pre-operative sessions of vestibular LiSWT immediately prior to complete subepithelial vestibulectomy surgery; they used significantly fewer opioids post-op than those without pre-operative LiSWT based on historical data prior to 2019. All patients received multiple LiSWT sessions to maximize mechanotransduction effects on genital tissues. There were no significant adverse events noted with LiSWT use. Conclusions Multiple LiSWT sessions are utilized in individuals with vulvas with sexual dysfunction to maximize mechanotransduction. LiSWT is associated with improved sexual health symptoms ranging from 54% - 75%, not associated with any side effects. More research is needed regarding the role of LiSWT for management of various sexual dysfunctions. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Softwave TRT.

M2 Macrophage Polarization and Tissue Remodeling in Autologous Fat Grafting for Diabetic Skin Defects.

Autologous adipose tissue was recognized as a promising therapeutic option for soft tissue defects owing to its regenerative potential and ability to facilitate tissue reconstruction. However, the mechanisms by which autologous fat grafting (AFG) promotes healing remain unclear, hindering its potential applications. This study aimed to investigate the distribution and phenotypic transition of infiltrating macrophages in transplanted adipose tissue, as well as their correlation with diabetic skin defect remodeling. Streptozotocin-induced diabetic rats with full-thickness dorsal skin defects were included in this study. The transplanted adipose tissue at the skin defects was collected and analyzed using flow cytometry to determine macrophage proportion and phenotype. The healing of skin defects was evaluated, and treatment was continued until day 14 as the designated endpoint of healing, followed by histopathologic examinations. Immunostaining with CD31 and lymphatic vessel endothelial receptor-1 was performed on wound tissues to analyze angiogenesis and lymphangiogenesis, respectively. Western blot and quantitative polymerase chain reaction analyses were used to assess the expression of the representative genes involved in the healing process. The results showed early polarization of M2 macrophages in the transplanted adipose tissue, concomitant with the upregulation of growth factors and downregulation of inflammatory factors. In vivo experiments revealed that AFG significantly promoted macrophage infiltration and M2 transformation in diabetic skin defects compared to the control groups, thereby promoting tissue extracellular matrix remodeling and lymphatic and vascular regeneration. However, the beneficial effects of AFG were inhibited by macrophage depletion. This study further demonstrated the potential of AFG for treating diabetic skin defects.

Can Plant Extracts Help Prevent Hair Loss or Promote Hair Growth? A Review Comparing Their Therapeutic Efficacies, Phytochemical Components, and Modulatory Targets

This narrative review aims to examine the therapeutic potential and mechanism of action of plant extracts in preventing and treating alopecia (baldness). We searched and selected research papers on plant extracts related to hair loss, hair growth, or hair regrowth, and comprehensively compared the therapeutic efficacies, phytochemical components, and modulatory targets of plant extracts. These studies showed that various plant extracts increased the survival and proliferation of dermal papilla cells in vitro, enhanced cell proliferation and hair growth in hair follicles ex vivo, and promoted hair growth or regrowth in animal models in vivo. The hair growth-promoting efficacy of several plant extracts was verified in clinical trials. Some phenolic compounds, terpenes and terpenoids, sulfur-containing compounds, and fatty acids were identified as active compounds contained in plant extracts. The pharmacological effects of plant extracts and their active compounds were associated with the promotion of cell survival, cell proliferation, or cell cycle progression, and the upregulation of several growth factors, such as IGF-1, VEGF, HGF, and KGF (FGF-7), leading to the induction and extension of the anagen phase in the hair cycle. Those effects were also associated with the alleviation of oxidative stress, inflammatory response, cellular senescence, or apoptosis, and the downregulation of male hormones and their receptors, preventing the entry into the telogen phase in the hair cycle. Several active plant extracts and phytochemicals stimulated the signaling pathways mediated by protein kinase B (PKB, also called AKT), extracellular signal-regulated kinases (ERK), Wingless and Int-1 (WNT), or sonic hedgehog (SHH), while suppressing other cell signaling pathways mediated by transforming growth factor (TGF)-β or bone morphogenetic protein (BMP). Thus, well-selected plant extracts and their active compounds can have beneficial effects on hair health. It is proposed that the discovery of phytochemicals targeting the aforementioned cellular events and cell signaling pathways will facilitate the development of new targeted therapies for alopecia.

Abstract 722: A cancer-associated fibroblast model to discover mechanisms of growth, survival, and treatment sensitivity in PAX3/7-FKHR fusion-positive alveolar rhabdomyosarcoma

Abstract Introduction: Rhabdomyosarcoma (RMS) is the most common pediatric soft tissue sarcoma. Among various subtypes, alveolar RMS (ARMS) is generally more aggressive and usually carries the fusion transcription factor, PAX3/7-FKHR. High-risk ARMS has an extremely poor prognosis, with ~25% five-year survival. Hence, novel therapeutic approaches are urgently needed. However, potential therapies are often hindered by the immunosuppressive tumor microenvironment (TME) associated with sarcomas. The TME is highly dynamic and includes fibroblasts, immune cells, and extracellular matrix. Cancer-associated fibroblasts (CAFs) may promote tumor growth and survival by secreting distinct factors to regulate proliferation, metastasis, and resistance to therapy. In this study, we investigated mechanisms involved in this phenomenon and identified a novel therapeutic strategy targeting the TME of ARMS. Methods: Cells were isolated from a PAX3-FKHR fusion-positive ARMS tumor specimen, following ethics approval and informed consent. The PAX3-FKHR fusion status and mesenchymal biomarkers were analyzed by immunoblotting. The patient’s CAFs (designated KCCF14), RMS lines (RD, RH30, RH41), and control fibroblasts (BJ, HS68, WI-38) were cultured in vitro and their respective supernatant media was harvested for subsequent experiments. Cell proliferation and viability were determined by hemocytometer and alamar blue assay, respectively. The scratch wound healing assay was used to assess cell migration. Cytokine analysis was performed with a 96-plex array. For drug screening, cells were treated with a panel of CXCR4 antagonists to generate dose-response curves. Results: KCCF14 CAFs isolated from an ARMS tumor exhibit elongated spindle morphology and are positive for mesenchymal biomarkers, including PDGFR-β and smooth muscle α-actin. As expected, these cells lack characteristics of the patient’s tumor, notably the expression of PAX3-FKHR fusion and N-myc. KCCF14-conditioned media significantly enhances ARMS cell proliferation and migration in a concentration-dependent manner. Analysis of the conditioned media revealed upregulation of key growth factors and cytokines, including PDGF-AA, VEGF-A, MCP-1, and IL-11, that promote tumor aggressiveness through proliferative signaling, angiogenesis, activation of migration, and immune evasion. Because SDF-1 (CXCR4 ligand) was also increased, we tested targeted inhibition of CXCR4, which induced cytotoxicity with increased sensitivity (IC50 = 0.5 µM) in KCCF14 cells compared to control fibroblasts. Conclusions: This study provides, for the first time, findings from a continuously growing CAF model system for RMS. Our data describes key tumor growth and survival mechanisms supported by the TME and establishes a method to identify treatments with novel therapeutic strategies. Citation Format: Patrick Sipila, Son Tran, Chunfen Zhang, Anne–Marie Langevin, Aru Narendran. A cancer-associated fibroblast model to discover mechanisms of growth, survival, and treatment sensitivity in PAX3/7-FKHR fusion-positive alveolar rhabdomyosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 722.

Abstract 5527: Spatiotemporal analysis of growth factor regulation of osteosarcoma AKT and ERK signaling dynamics in an ex vivo lung metastasis model

Abstract In the present study, we investigated the relationships between spatiotemporal distribution of growth factors in the lung microenvironment, metastatic osteosarcoma cell signaling, and intratumoral gene expression heterogeneity. Osteosarcoma is an aggressive bone malignancy that commonly metastasizes to the lungs, resulting in significant patient mortality. During metastasis, disseminated cancer cells are exposed to microenvironment-derived growth factors that result in signaling pathway activation. Two such pathways are MAPK/ERK and PI3K/AKT, which regulate complex transcriptional programs underlying cell proliferation and survival decisions. In this study, we utilized precision cut lung slices (PCLS) obtained from mice with established osteosarcoma metastases to ex vivo model associations between the spatiotemporal distributions of growth factors in the lung, osteosarcoma signaling dynamics, and intratumoral gene expression heterogeneity, with single cell precision. To accomplish this, we engineered osteosarcoma cells that co-expressed genetically-encoded ERK and AKT sensors, engrafted them into PCLS tissues, then recorded sensor dynamics via live-cell microscopy. These tissues were subsequently fixed and immuno-stained for measurement of growth factor expression in resident lung cells and spatial correlation with observed tumor cell ERK-AKT signaling dynamics. Using this approach, we found that growth factor expression was diffusely increased within areas bordering osteosarcoma metastases. FGF2 and IGF1, which we have previously demonstrated to potently induce ERK signaling in osteosarcoma cells, were both significantly upregulated in these regions. However, despite relatively uniform overexpression of growth factors adjacent to tumors, individual osteosarcoma cells displayed stochastics patterns of ERK and AKT signaling, and downstream gene targets. These findings revealed that upregulation of lung growth factors, and the inherent systems-level properties of osteosarcoma signaling networks, can converge to promote intratumoral signaling and gene expression heterogeneity. Together, our results, using a novel PCLS and live-cell biosensor imaging approach, provide new insight into how spatial and temporal changes in microenvironmental signaling composition are integrated by metastatic osteosarcoma cells to promote heterogeneity. Citation Format: Rawan Makkawi, Ryan D. Roberts, Jeremy Copperman, Alexander E. Davies. Spatiotemporal analysis of growth factor regulation of osteosarcoma AKT and ERK signaling dynamics in an ex vivo lung metastasis model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5527.

Sodium alginate/polyvinyl alcohol nanofibers loaded with Shikonin for diabetic wound healing: In vivo and in vitro evaluation

Diabetic wounds are typically chronic wounds and the healing process is limited by problems such as high blood glucose levels, bacterial infections, and other issues that make wound healing difficult. Designing drug-loaded wound dressings is an effective way to promote diabetic wound healing. In this study, we developed an SA/PVA nanofiber (SPS) containing Shikonin (SK) for the treatment of diabetic wounds. The prepared nanofibers were uniform in diameter, had good hydrophilicity and high water vapor permeability, and effectively promoted gas exchange between the wound site and the outside world. The results of in vitro experiments showed that SPS was effective in antimicrobial, antioxidant, and biocompatible. In vivo tests showed that the wound healing rate of mice treated with SPS reached 85.5 %. Immunohistochemical staining results showed that SPS was involved in the diabetic wound healing process through the up-regulation of growth factors (CD31, HIF-1α) and the down-regulation of inflammatory factors (CD68). Western blotting experiments showed that SPS attenuated the inflammation through the inhibition of the IκBα/NF-κB signaling pathway. These results suggest that SPS is a promising candidate for future clinical application of chronic wound dressings.

Abstract WP299: Encephalomyosynangiosis Promotes Mature Angiogenesis After Ischemic Stroke

Backgrounds: Current treatments for ischemic stroke patients is ineffective. The brain's inherent ability to self-heal post ischemic stroke is hampered by inadequate blood supply to the affected region. Encephalomyosynangiosis (EMS), a neurosurgical intervention, has proven successful in promoting angiogenesis in patients with Moyamoya disease. We have earlier shown that EMS can increase angiogenesis after stroke in the implanted region, it is not known if those blood vessels are stable or mature. Given that EMS provide balanced growth factors, we therefore hypothesized that EMS enhances stable or mature cerebral angiogenesis in the cortical region surrounding the muscle graft. Methods: Following a 60-minute period of transient middle cerebral artery occlusion (MCAo), mice were assigned randomly to either MCAo alone or MCAo followed by EMS (3-4 hours post MCAo).. Mice were sacrificed at 7, 21, or 70 days post MCAo. A mouse angiogenesis and proteomic profile array was employed to quantify the expression of angiogenic and neuromodulating proteins. Immunohistochemistry was utilized to visualize the bonding of the graft with the brain cortex, changes in vessel density, and pericyte coverage to assess the degree of normal or mature angiogenesis. Results and Conclusions: Preliminary data indicate successful graft implantation and a significantly increased vessel density (P<0.05 compared to the MCAo alone) in proximity to the muscle graft, signifying increased angiogenesis after stroke. EMS-treated mice exhibited an early improvement in sensory motor deficits post-stroke. Analysis of the angiogenesis and proteomic profile array data unveiled a downregulation of antiangiogenic factors (such as interleukin-10 and Fetuin A) and an upregulation of pro-angiogenic cytokines or growth factors (including Fibroblast Growth Factor and C-X-C Motif Chemokine 12) in the EMS group. Co-immunostaining of the endothelial cell marker (Lectin) with the pericyte marker Platelet-Derived Growth Factor Receptor Beta (PDGFRβ) after 70 days of EMS suggested the stability and maturity of new blood vessels. In summary, the EMS procedure appears effective, holding promise for enhanced stable angiogenesis which may help to expedite recovery following ischemic stroke.

Graft-Host Interaction and Its Effect on Wound Repair Using Mouse Models.

Autologous skin grafting has been commonly used in clinics for decades to close large wounds, yet the cellular and molecular interactions between the wound bed and the graft that mediates the wound repair are not fully understood. The aim of this study was to better understand the molecular changes in the wound triggered by autologous and synthetic grafting. Defining the wound changes at the molecular level during grafting sets the basis to test other engineered skin grafts by design. In this study, a full-thickness skin graft (SKH-1 hairless) mouse model was established. An autologous full-thickness skin graft (FTSG) or an acellular fully synthetic Biodegradable Temporising Matrix (BTM) was grafted. The wound bed/grafts were analysed at histological, RNA, and protein levels during the inflammation (day 1), proliferation (day 5), and remodelling (day 21) phases of wound repair. The results showed that in this mouse model, similar to others, inflammatory marker levels, including Il-6, Cxcl-1, and Cxcl-5/6, were raised within a day post-wounding. Autologous grafting reduced the expression of these inflammatory markers. This was different from the wounds grafted with synthetic dermal grafts, in which Cxcl-1 and Cxcl-5/6 remained significantly high up to 21 days post-grafting. Autologous skin grafting reduced wound contraction compared to wounds that were left to spontaneously repair. Synthetic grafts contracted significantly more than FTSG by day 21. The observed wound contraction in synthetic grafts was most likely mediated at least partly by myofibroblasts. It is possible that high TGF-β1 levels in days 1-21 were the driving force behind myofibroblast abundance in synthetic grafts, although no evidence of TGF-β1-mediated Connective Tissue Growth Factor (CTGF) upregulation was observed.

Malignant Peripheral Nerve Sheath Tumors Activate Distinct Immunosuppressive Pathways Following Radiotherapy and are Associated with Immune Depletion In Vivo

Patients with neurofibromatosis type I, caused by NF1 loss, develop benign plexiform neurofibromas (pNF) in their peripheral nervous system (PNS). Malignant transformation of pNFs into malignant peripheral nerve sheath tumors (MPNSTs) occurs following CDKN2A/B and SUZ12 loss, a process associated with radiotherapy (RT). However, the molecular mechanisms underlying RT responses by different PNS cell types remain unclear. We hypothesized normal peripheral nerve cells, pNFs, and MPNSTs harbor distinct RT responses. Patient derived NF1 WT immortalized peripheral nerve cells (iPNs), NF1 mutant pNF cells, and NF1/CDKN2AB/SUZ12 mutant MPNST cells were used to study RT responses in vitro. CRISPRi was used to assess the functional effects of candidate gene repression. In vitro viability was measured by cell counts. Transcriptomic signatures were measured by bulk RNA-sequencing and integrated with single-cell RNA sequencing (scRNA-seq) data from patient-derived pNF and MPNST resection specimens. Radiation dose response curves revealed pNF cells (IC50 0.61 Gy) were more radiosensitive than MPNST cells (4.15 Gy). WT iPNs, NF1 deficient iPNs, and pNFs cells displayed no difference in cell viability (p = 0.67; t-test) following initiation of 2 Gy x 5 fractions, while MPNST cells were significantly more viable (p = 0.02; t-test). Principal component analysis of bulk RNA-sequencing data at 5 or 14 days following 2 Gy x 5 fractions revealed cell line of origin accounted for the greatest inter-sample variation (64.9% variance), with additional components separating samples based on radiation presence and timing. Using the most variable genes in PCA space to identify markers of RT response, iPNs and pNFs upregulated pro-apoptotic pathways (BAD, DAPK3) at 5 days post-radiation while MPNST cells alone upregulated pro-survival growth factor signaling). At 14 days post radiation, MPNST cells uniquely upregulated TGFβ signaling and interferon response circuits. Incorporation of scRNA-seq data revealed enrichment of growth factor signaling and TGFβ signatures in MPNSTs compared to pNF. Moreover, MPNST harbored significantly fewer immune cells than pNFs (p = 0.008, t-test), suggesting cell-autonomous signaling and crosstalk with the microenvironment are both critical to MPNST radioresistance. Our data indicate additional genetic hits beyond NF1 loss may be required for RT-associated malignant transformation of pNFs and radioresistance in MPNSTs. Analysis of transcriptomic responses to RT suggests that upregulated growth factor signaling and TGFβ-associated immunosuppression are distinct features of MPNST. Future work will focus on CRISPRi screens to unbiasedly nominate functional modifiers of RT response in NF1/CDKN2AB deficient tumors, which may be broadly useful in cancer.

Short-term changes of angiogenesis factors after transarterial radioembolization in hepatocellular carcinoma patients.

To analyze changes in angiogenesis factors after transarterial radioembolization (TARE) with Yttrium- 90-loaded resin microspheres in hepatocellular carcinoma (HCC) patients. Interleukin-6, interleukin-8, hepatocyte growth factor, platelet-derived growth factor, fibroblast growth factor, vascular endothelial growth factor-A (VEGF-A), and angiopoietin-2 levels in 26 patients were measured before TARE and on day 1, 7, 14, and 30 after TARE and evaluated regarding radiological response. In the sixth month of follow-up, 11 (42.30%) patients had a complete or partial response to treatment, while progressive disease was found in 15 (57.69%) patients. The percentage changes in VEGF-A in the non-responders on day 30 (P = 0.034) after TARE were significantly more obvious. Peak formation rates of VEGF-A were higher in non-responders (P = 0.036). Short-term changes in angiogenesis factors in HCC patients after TARE with Yttrium-90-loaded resin microspheres fluctuate with different amplitudes at different times. The upregulation of growth factors has a prognostic capacity. Changes in VEGF-A after TARE may be helpful for the early recognition of non-responders.

Effectiveness of Collagen Extracted From the Skin of Nile Tilapia Fish (Oreochromis niloticus) to Accelerate Wound Healing in vivo: A Narrative Review

Developing wound dressings with good properties to accelerate wound healing has always been challenging. Mammal collagen is well known as the desired choice among naturally produced dressings despite experiencing major drawbacks. Therefore, researchers have explored the by products of Oreochromis niloticus fish or red Nile tilapia, such as the scales and skin as alternative source of collagen. This narrative review analyzes the effectiveness of collagen extracted from Oreochromis niloticus skin and its beneficial properties to accelerate wound healing in vivo. Recent studies were compiled to provide a compact review on the effectiveness of the collagen in hastening wound healing process. Faster wound closure with upregulation of multiple growth factors, and high hydroxyproline content are some of the findings. The collagen extract could also promote the formation of epidermal layers, fibroblasts proliferation, and dermal reconstitution. Thus, Oreochromis niloticus skin collagen extract has the potential to be developed as an effective wound dressing.

Multifaced roles of desmoplastic reaction and fibrosis in pancreatic cancer progression: Current understanding and future directions.

Desmoplastic reaction is a fibrosis reaction that is characterized by a large amount of dense extracellular matrix (ECM) and dense fibrous stroma. Fibrotic stroma around the tumor has several different components, including myofibroblasts, collagen, and other ECM molecules. This stromal reaction is a natural response to the tissue injury process, and fibrosis formation is a key factor in pancreatic cancer development. The fibrotic stroma of pancreatic cancer is associated with tumor progression, metastasis, and poor prognosis. Reportedly, multiple processes are involved in fibrosis, which is largely associated with the upregulation of various cytokines, chemokines, matrix metalloproteinases, and other growth factors that promote tumor growth and metastasis. Fibrosis is also associated with immunosuppressive cell recruitment, such as regulatory T cells (Tregs) with suppressing function to antitumor immunity. Further, dense fibrosis restricts the flow of nutrients and oxygen to the tumor cells, which can contribute to drug resistance. Furthermore, the dense collagen matrix can act as a physical barrier to block the entry of drugs into the tumor, thereby further contributing to drug resistance. Thus, understanding the mechanism of desmoplastic reaction and fibrosis in pancreatic cancer will open an avenue to innovative medicine and improve the prognosis of patients suffering from this disease.

Nano hydrogel-based oxygen-releasing stem cell transplantation system for treating diabetic foot

The employment of stem cells and hydrogel is widespread in contemporary clinical approaches to treating diabetic foot ulcers. However, the hypoxic conditions in the surrounding lesion tissue lead to a low stem cell survival rate following transplantation. This research introduces a novel hydrogel with superior oxygen permeability and biocompatibility, serving as a vehicle for developing a stem cell transplantation system incorporating oxygen-releasing microspheres and cardiosphere-derived stem cells (CDCs). By optimizing the peroxidase fixation quantity on the microsphere surface and the oxygen-releasing microsphere content within the transplantation system, intracellular oxygen levels were assessed using electron paramagnetic resonance (EPR) under simulated low-oxygen conditions in vitro. The expression of vascularization and repair-related indexes were evaluated via RT-PCR and ELISA. The microspheres were found to continuously release oxygen for three weeks within the transplantation system, promoting growth factor expression to maintain intracellular oxygen levels and support the survival and proliferation of CDCs. Moreover, the effect of this stem cell transplantation system on wound healing in a diabetic foot mice model was examined through an in vivo animal experiment. The oxygen-releasing microspheres within the transplantation system preserved the intracellular oxygen levels of CDCs in the hypoxic environment of injured tissues. By inhibiting the expression of inflammatory factors and stimulating the upregulation of pertinent growth factors, it improved the vascularization of ulcer tissue on the mice’s back and expedited the healing of the wound site. Overall, the stem cell transplantation system in this study, based on hydrogels containing CDCs and oxygen-releasing microspheres, offers a promising strategy for the clinical implementation of localized stem cell delivery to improve diabetic foot wound healing.

Inhibition of Interleukin-6 Dependent Metalloproteinases-9/2 Expression in Cancer Cells by Diet Polyphenols.

Among inflammatory cytokines, Interleukin-6 (IL-6) is one of the major activators of acute phase response and is also involved in immune response and cancer progression. IL-6 is involved in the up-regulation of enzymes and growth factors acting on the extracellular matrix (ECM) remodelling components in physio-pathological processes. IL-6 enhances the expression of metalloproteases (MMP-)2/9, enzymes that play a key role in ECM degradation and therefore contribute to the process of tumor metastasis. To counteract and/or prevent cancer diseases, many efforts have been devoted to the identification of factors able to inhibit the IL-6-dependent MMP-9/2 expression. Recently, diet polyphenols have been identified as molecules manifesting anti-inflammatory and anti-cancer properties beyond their well-known capacity to promote health on the basis of their antioxidant effects. This review summarizes the recent advances in this field, focusing on the protective effects exerted by diet polyphenols on the proliferation and invasiveness of tumor cells, with specific emphasis on the ability of these molecules to inhibit the IL-6-dependent upregulation of MMP-2/9.